Remember falling population will be happening at a time of increasing robotics in western countries at least, which may tend to keep per capita consumption high for some specific goods and services. (realclimate.org)
Fall population of waterfowl peaks at over 263,000 birds (powercouplelife.com)
1) Lower or zero population growth makes huge sense to me and even falling population could be ok within reason, although we have to be careful not to enter some spiral. (realclimate.org)